docs: def heightmap_add_fbm(
      hm: np.ndarray,
      noise: tcod.noise.Noise,
      mulx: float,
      muly: float,
      addx: float,
      addy: float,
      octaves: float,
      delta: float,
      scale: float,
  ) -> None:
      """Add FBM noise to the heightmap.
  
      The noise coordinate for each map cell is
      `((x + addx) * mulx / width, (y + addy) * muly / height)`.
  
      The value added to the heightmap is `delta + noise * scale`.
  
      Args:
          hm (numpy.ndarray): A numpy.ndarray formatted for heightmap functions.
          noise (Noise): A Noise instance.
          mulx (float): Scaling of each x coordinate.
          muly (float): Scaling of each y coordinate.
          addx (float): Translation of each x coordinate.
          addy (float): Translation of each y coordinate.
          octaves (float): Number of octaves in the FBM sum.
          delta (float): The value added to all heightmap cells.
          scale (float): The noise value is scaled with this parameter.
  
      .. deprecated:: 8.1
          An equivalent array of noise samples can be taken using a method such
          as :any:`Noise.sample_ogrid`.
      """
      noise = noise.noise_c if noise is not None else ffi.NULL
      lib.TCOD_heightmap_add_fbm(
          _heightmap_cdata(hm),
          noise,
          mulx,
          muly,
          addx,
          addy,
          octaves,
          delta,
          scale,
      )